books.google.com - Taking a slightly different approach from similar texts, Introduction to Abstract Algebra presents abstract algebra as the main tool underlying discrete mathematics and the digital world. It helps students fully understand groups, rings, semigroups, and monoids by rigorously building concepts from first...http://books.google.com/books/about/Introduction_to_Abstract_Algebra_Second.html?id=PQUAQh04lrUC&utm_source=gb-gplus-shareIntroduction to Abstract Algebra, Second Edition